Broad coke oven



March 11, 1941. c, HUGHES 2,234,171

BROAD coma OVEN Filed 001;. 25, 1939 6 Sheets-Sheet 3 March 11, 1 941. c, HUGHES 2,234,171

snow com: OVEN 4 Filed Oct. ,25, 1959 6 Sheets-Sheet 4 March 11, 1941. Q s 2234171 BROAD COKE OV EN Filed Oct. 25, 1939 6 Sheets-Sheet '5 g/aswj Q ki N EY March 11, 1941. c, HUGHES 2,234,171

BROAD COKE OVEN Filed Oct. 25, 1939 6 Sheets-Sheet 6 ORNEY Patented Mar. 11, 1941 UNITED STATES PATENT OFFICE Hughes By-Product Coke Oven Corporation,

New York, N. Y., a corporation of New York Application October 25, 1939, Serial No. 301,172

.13 Claims.

coking coal. in a regular oven is an English patent to St. John granted in 1620 for making coke in a beehive form of oven. Although a German chemist, Becher, received a patent in 1700 for recovering tar from coking coal, it appears that 5 it was not until Claytons discovery .in 1737 that the formation of a combustible gas when coking coal was noticed. About the year 1767, a form of coke oven, producing coke and recovering some.

tar and ammonia, was constructed in Germany and was described as a dome-like fire clay retort. In 1781, an attempt appears to have been made to recover the by-p-roducts, and a patent to the Earl of Dundonald was issued, and in 1792 Murdoch experimented with making gas from coal in retorts. These efforts bore fruit, and twenty years later the streets of London were lighted by gas.

The earliest records of the rectangular, or retort, ovens show them in operation in Germany about 1830. They had open walls, pierced by horizontal and vertical fiues, and the walls formed a rectangular space which contained the charge. In 1856, Knab is reported to have built a group of retort coke ovens to recover by-products and illuminating gas. These ovens had flues on the bottom only, but, of course, no regenerator or recuperator system was provided. Moreover, there was no attempt to furnish uniform heating to the oven sole, the fire or flame passing from a grate through a central flue and then returning through fiues on both sides thereof. The following year, Appolt built his first ovens in the shape of vertical and, later, horizontal retorts, using his gas only for heating his oven through horizontal fiues. This was about the earliest closed retort coke oven, utilizing the gas for its own heating. By 1861 the- Coppee coke oven of ill Belgian invention was in use on the Continent, and in 1873-74 it was introduced into England. It had vertical fines and was of the non-recovery type.

About 1862 Carves of France introduced side lines in addition to the bottom fiues of Knab. About 1880, Simon. an English inventor. im-

proved the Carves oven very materially by adding recuperating flues. This oven had the oven flues placed horizontally, the gas and air being first burned in sole fl'aes located underneath the oven chamber, then passing up through a riser to the ovens and down through three, horizontal dues in series. In the years 1881 to 1883, Seibel patented an oven having horizontal flues and having neither grates nor regenerators. It is apparent that oven designs up to this time were so uneconomical of gas used in heating the ovens, or the coals were so lean in gas, that grates for burning vcoal were built into the ovens and the gas was first admitted over these grates, the amount of coal being such as to supply the required additional heat.

The first ovens of the Otto type had been erected in Germany in 1881, and in the same year Huessner appropriated the Knab-Carves model and built a hundred ovens in Germany, thus establishing the industry on a sound basis in that country, although the quality of coke from these ovens was inferior. In these ovens the flues were horizontal. A very substantial improvement was made by Hoffman, who added the Siemens regenerator to the Otto coke oven and thus provided the first really efficient coke oven, generally referred to in the art as the Otto-Hoffman coke oven. In 1888 Festner, a German inventor, changed the Otto-Hoffman design by using horizontal instead of vertical flues and abandoning the Siemens regenerators, replacing the same with a Ponsarcl gas furnace. Hoffman cooperated with Festner, and this design was called a Festner-Hofiman oven, having horizontal flues and recuperators. In 1887, the Semt-Solvay oven came into notice, the first of them having no recuperators-or regenerators. It appears that somefof the principal features of Semets design were the introduction of the division wall, the building of the oven flue system as a sleeve out of D-shaped tile, and the starting of the combustion at the top, or No. 1, flue, and, in general, providing a structure which was, strong, easily heated and had a reservoir of heat in the division walls.

From the foregoing historical survey of the development of the coke oven art, itappears that all designs of ovens for coking coal sprang from four roots classified as follows:

1. The beehive oven, which was developed from the mound of charcoal burners.

2. The Coppee oven,with vertical lines in the length, about 16 feet high, and about 17 inches in width, and, because of their height and narrowness, they had to be constructed and built in very large individual units, so that'the original cost of installation was extremely high. Generally speaking, it was not possible either to build or to operate relatively small units of the conventional type at a low cost. I

Besides these economic disadvantages, the use of a high, narrow oven was limited to certain coals or coal mixtures. Coals which expanded upon coking could only. be used if mixed with shrinking coals, as otherwise the wear on the walls was too great, and the increasing pressure might have led to destruction of the ovens. Using a large percentage of shrinking coals, as

', necess arily 'became general practice, the coal shrank away from the heating walls, causing the formation between coke and wall of irregular .gaps and crevices which acted as channels for Ithe gases distilled from the coal. Due to the irregularity of these channels, heat could not be applied so as to produce a uniformly carbonized coke, in a short coking period, regardless of the method of heating or control employed.

It is well known in the'art that this channel- V ing brought the rich gases into immediate contact with the highly ,heated refractory walls, producing two unfortunate results. First, the

contact of the crude gases with some 1440 square feetof brick at the highest temperature in the oven caused the destruction of a part of the valuable by-products contained in the gases. Secondly, the gases acted. as an insulator between the hot walls and the coking coal, preventing considerable heat' from reaching the charge by conduction. Again, the gases, being much lower in ing surfaces to cool them.

a temperature than the walls, took up considerable heat from them and thus prevented this amount of heat from reaching the core of the charge at all. Both ofthese effects resulted in greatly retarding the coking time and were diametrically opposed to the results desired, for it was, of

course, the purpose of the operation to transfer heat from walls to coal charge as efllciently as possible andin the shortest time. Moreover, the

heating ofthe gases had the undesirable effect of passingthe'gases to the'by-product plant in asuperheate'd state, necessitating larger condens- A further disadvantage of the high, narrow coke oven was that the width of the charge varied overthe length of the oven, for practical reasons being smaller at the pusher end than at the coke discharge end. In order to-provide for uniform coking throughout this constantly vary ing oven width, more gas had to be burned in the fines at the coke end of the oven, necessitating a diflerence in size of heating flues over the length of the oven This required very accurate control of the fuel gas to theindividual fiues.

Under these conditions, it was difficult to control heating conditions in these ovens, the ovenstructure was intricateand expensive, resulting in high-cost coke, and the coke produced was primarily suitable only for metallurgical purposes and not for domestic use. Subsequently, a broad rectangular sole-fired coke oven attempting to eliminate these disadvantages and to coke coal at a lower cost was developed, but other difficulties arose.

Essentially, this broad oven construction provided a rectangular sole-fired coke oven having a multiplicity of long, independent, parallel heating flues arranged side by side, each of said flues being directly connected at each end to two shallow, horizontal hair-pin regenerators below and parallel to and individual to each separate heating flue for alternately supplying heated air to the flues and receiving the heat of waste gases discharged therefrom. Each heating flue was provided with a burner or means for supplying rich fuel gas to both ends thereof. In this manner all of the flames burned in independent and isolated flues in the same direction and extended from one end toward the other end of the oven. Thus, each heating flue and its associated regenerators could be alternately operated, independently of adjoining heating fines and regenerator's.

Although this type of broad oven could be built in relatively small units, the entire heating system and the' so-called regenerators were fundamentally incorrect. The oven was designed for underfiring with rich coke oven gas only. The use of coke oven gas with preheated air gave a short and hot flame resulting in non-uniform heating of the long, straight, parallel and independent heating fiues. An excessively high temperature-occurred at each burner, producing In'other words, .by eliminating some of the disadvantages of prior ovens, the broad oven described introduced new difiiculties which were in part much more serious than the former. Thus, the ends of the heating flues in said broad oven were overheated, causing overcoking and quick overheating of the construction material of the oven, while black spots, too cold for proper coking, developed in the centers of the fines. Clearly, it was practically impossible to obtain proper coking of the center mass except, and then to only av small extent, by overcoking the masses at the ends 'of the flues. Then, the space provided above and below the regenerators was inadequate for the gases to spread or mushroom out before going through the checkerbrick. Moreover, the regenerators, which were individual for each flue, were insufficient in size and could not function satisfactorily. The velocity of the gases in the heating flues was too slow and in the regenerator too high for proper heat transfer. Of course, not only did this non-uniform-d'istribution of hat greatly decrease the over-all eificiehcy of these ovens, but, especially, the hot spots, developed in the operation of the oven, caused early deterioration of the building material and greatly increased the cost of operation and maintenance. Although these difiiculties were well known in the art, and, from time to time, various'sug gestions and proposals were made to eliminate them, none of these suggestions and proposals, so far as I am aware, was completely satisfactory and sucn cessful on a practical and industrial scale.

lem may be solved in a simple and completely satisfactory manner.

It is an object of the present invention to provide a by-product coke oven which eliminates the aforementioned diiiiculties in the construction and operation of conventional broad coke ovens.

It is another object of this invention to provide a by-product coke oven in which various coals, tars and oils can be used to produce a coke substance with burning characteristics different from those of coke produced heretofore in high, narrow ovens or beehive coke ovens.

It is a further object of the invention to provide a by-product coke oven of novel and improved character providing an increased and positive control of the air to be preheated and of the waste gas from the oven.

It is also an object of the invention to incorporate in broad ovens a novel combination of structural elements which are arranged to cause the air which is being heated to ascend and to cause the gas which is being cooled to descend, whereby uniformiti of flow and an effective change of temperature of the different streams are obtained.

The invention also provides a broad coke oven having a series of interdependent and interconnected heating flues extending in a single, continuous, serpentine character 'under the entire sole of the oven to afford a continuous stream of the heating fluid throughout the whole heating system, and having a multiplicity of burners in the series to furnish a more. on less continuous flame throughout, whereby uniform heating conditions in all parts of the charge are obtained.

Still another object of the invention is to provide a coke oven having a system of heating principles of the present invention, taken on line I-l of Figs, 2 and 3;

Fig. 2 depicts a transverse vertical sectional view taken on line 2-2 of Fig. 1; Fig. 3 shows a front elevational view of the ovens, taken on line 3-3 of Fig. 1;

Fig. 4 isa vertical longitudinalsectional view through the oven and regenerators taken on line 4-4 of Fig. 1;

Fig. 5 illustrates a front elevational view taken on line 5 5 of Fig. 1, depicting the arrange ment of the closed valve boxes on the coke side of the oven battery;

Fig. 6 depicts a front elevational view taken on line 6-6 of Fig. 1 andgshowing the arrangement of the open valve boxes on the pusher side of the oven battery;

Figs. '7, 8, 9 and 10 show the details of the combination air and waste gas valve employed in the coke oven of the invention;

Fig. 11 is a flow diagram showing the five uneven number of sole flues, preferably flve, in-

terconnected in series and arranged to support and to heat the floor of the oven. Each oven can be operated independently of the adjoining ovens These heating fiues are connected by openings located at opposite ends with two sets of verthe heating flues and coke ovens.

flues so. designed as to conduct the products of combustion to each, succeeding flue in series for the purpose .of using said waste products to prevent high heats or hot spots in thevicinity of the fuel burners and to lengthen the flame by means of the increased velocity necessary for' proper heat transfer, the increased velo'city being due to the increased volume of gases constantly circulating through all heating fiues. i

A further object of the invention is to provide a by-product coke oven in which the direction/of flow of the hot gases through the heating flue system can be reversed, thereby insuring uniform heating over the entire floor of the oven.

The invention also contemplates the arrangement of the gas burners in broad coke ovens'in such positions that the flames, which burn constantly and at both ,ends of the oven at the same time, will change direction with the reversal of gases through the heating fines, lashing back and forth from one flue ,to another.

It is also within the contemplation of the invention to provide a coke, oven of the broad rectangular type which can be economically built and operated in relatively small units on a practical and industrial scale and which is of high structural strength, thus imparting long life to the oven and-only requiring low maintenance charges.

Other and further objects and advantages of the invention will become apparent from the folical regenerators located below and parallel to The two sets of vertical regenerators are alternately used to supply preheated air-to opposite ends of the series flue heating system and to receive the hot waste products of combustion. These regenerators have spacious, chamber-like passages both above and below the checkerbrick, giving the gases an opportunity to spread or mushroom out before passing through and thus increasing the time of contact and affording more effective heat transfer. A combination air and waste gas box, equipped with the necessary valves, is provided on both the pusher and coke sidesof each oven for the accurate control of the air entering the regenerator and in order to control the draft for each oven. I

The invention will now be more fully described to those skilled in the art, reference being had to the accompanying drawings illustrating a preferred embodiment of the present invention. Similar reference characters denote identical parts throughout the various flgures.

Referring, now, more specifically tdFigs; l to 4, reference characters I, 2, 3, 4 and 5 denote the heating flues, arranged in horizontal position, running parallel to the length, of the oven, and connected in series under the floor of the oven. The interconnected heating lines are provided with burning means, such as gas burners, B-l, B--2, B--3 and B-l which are supplied with fuel gas under a moderate and constant pressure. through ,suppiy manifolds F-l and F2 (Fig. 4). The fuel gas is conducted through pipes Gl and (3 -2 (Fig.4) to burners B-l, B-2, B--3 and 13- 1 (Fig. 1), and the fuel gas is regulated through a special T and an orifice (Fig. 12). Below each oven are located two sets of regenerators R-l, R2 and 18-3, Rl,

I built of standard checker brick or special checker brick in the vusual manner. R,I and R.-2 are connected with series flue P-8, inclusive.

Regenerators The alternate flow of waste gas and air and the circulation through the heating flues, regenerators and waste gas fines are controlled by 1 the reversing dampers in the valve boxes, as will be more fully explained hereinafter. (See Fig. 11.)

The valve boxes may be of any suitable design and appropriate construction, as those skilled in the art will readily understand. It is preferred, however, to use valve boxes of the type illustrated in Figs. 7 to 10. It is to be observed that'the preferred form of valve box has a single housing A, preferably a suitable metal casting, as of a corrosion-resistant material, such as alloy cast iron of the chrome type or the chromenickel type or the like. In the housing is mounted at the top thereof an air inlet damper or valve V--2 of rectangular shape, which, V--2|, is adapted to make a substantially air-tight contact with the seat V-22 of a rectangular port V-23 in the top of the box or housing. Slightly projecting shelves V on each of two opposite sides of the opening V--23 just below seat V-22 provide a seat upon which removable air-regulating bars B can be placed. The valve V--2 is supported by a valve stem V- -25 which is keyedto a rotatable shaft S-l. The shaft is held in position by a suitable sleeve mounting 8- -4 which is rigidly fastened to the housing. I

.Inside the housing of the valve box, a valve chest is formed, and withinthis valve chest is mounted a waste gas exit damper or valve D-2, the face D-2l of which is adapted to make a substantially air-tight contact with the seat D-22 of a port D-23 at the bottom of the box. This port forms the'upper end of passage or duct P-IB which connects the valve chamber with chimney flue C-2. The valve D--2 is supported by valve stem D- -25, which is keyed to a rotatable shaft vS- l. This shaft is mounted in a suitable sleeve mounting S-4, which is rigidly fastened to valve box A, and the shaft extends through the side of and outside the box.

Keyed to one end of rotatable shaft S-l is the fulcrum of a bell crank V-8. The bell crank has a straight arm which is connected by a suitable connection to a'cable C which runs aroundthe entire battery of ovens. The other arm of the bell crank is curved outward and over the edge of box A and at its end it connects with a vertical adjustable rod 8-3. This rod comprises three parts: the upper part S-3l connecting at the upper end thereof with the bell crank and with its lower end threaded; a turnbuckle S-32 which is screwed onto the threaded end of S-3l, and a lower part S-33 having either a swivel or a thread at its upper end adapted to coact with S32 and connected at its lower end to a lever V-4. Lever V4 is keyed to the end of shaft 8-2 which protrudes from the side of the valve box. The turnbuckle is adjusted to make rod 8-3 of such length that air valve V-2 is open when waste gas damper D-2 is tightly closed, and vice versa.

In passage P--I6 there is a rectangular plate damper D6 adapted to close off the passage in any degree required. It is mounted on a the face of r shaft S-6 which forms its longitudinal axis.

This shaft extends the width of the passage, and one end of it passes through a side of the passage. The shaft is suitably mounted in the sides of passage P-l6. To the end of shaft S-B which protrudes from the side, a quadrant Q is attached.

The reversing mechanism for operating the air and waste gas dampers is not shown, as those skilled in the art are familiar with the construction and operation. It may be briefly described as consisting of a motor driven drum around which the endless cable C is wound. A time clock, which is set for fixed reversal periods, is adapted to make the necessary electrical contacts required for starting and stopping the motor and for shifting the gears which change the direction of travel of cable C. The

cable is adapted for alternately opening and closing all dampers as required.

The same design of valve boxes, assembled right and left, as required, are used on both sides.

of the oven battery, andcable C, which extends around the entire oven battery, is wound around the motor drum and is adapted to travel in opposite directions at each side of the battery. Thus, all air inlet valves or dampers on the pusher side of the battery are open, and all waste gas dampers are closed; during the same reversal period, the air valves on the discharge side are closed, and the waste gas dampers are open, thus completing the circulation through the heating system and regenerators. The opposte is true during the alternate reversalper10 The operation of my improved broad coke oven will now be described, particularly in conjunction with Fig. 11, which illustrates diagrammatically the flow of gases through the several flues, ducts, regenerators, dampers and valves, for the convenience of those skilled in the art.

Assuming that the regenerators R,- I and R-2 are being preheated by the outgoing gases of combustion, valve V--l is closed and damper 13-! in passage P--8 is opened, permitting a flow of waste gas to chimney flue 0-4. The air to be preheated enters through valve V2, damper D--2 in passage P--I6 being closed. The air flows into passage P--l5, which is large enough to permit it to mushroom out, and then uniformly up through the hot checkerbrick in regenerator R-4 to passage P-M, whence by passages P-l3 and P--l2 the now partially heated air is brought to the spacious passage P-ll below reg enerator R-3. The air then passes up through the checkerbrick in regenerator R,3. This checkerbrick is hotter than that in regenerator R, 4, and the already heated air, on passing through, is brought to a very high temperature. It will be observed that provision of relatively large gas spaces above and below the regenerators permits the gas (here, air) to spread out before entering the checkerbrick andthus slows down its passage through the regenerators, giving improved heat transfer. The hot air passes along passage P-l0 above regenerator R,-3 and up passage P9 to heating flue I. This preheated air for the combustion of the fuel gas at the burners is delivered in flue I in great excess over the air requirements for burner Bl and, after the combustion at burner B-|, the air, still in considerable excess of the requirements of the next burner in the series, passes mixed with the products of combustion to burner 13-2, and similarly to all burners successively.

end of the oven,

, overcoking at the ends of the just opposite The hot waste gases of combustion pass out of the series flue heating system from flue 5 through passage P--l to passage P--2, which is sufficiently large for the gases to spread uniformly, and then downward. relatively slowly, through regenerator Rr"'-|. The waste gases are very hot at this point and give up a great deal of their heat to the checker-brick in regenerator R-l, becoming considerably cooler as they pass P-3 below the regenerator. brought through passages 6 above regenerator R-l, and thence go velocity through the checkerbrick in regenerator ft-2, to give up much of their remaining heat thereto and to emerge considerably cooler in passage P--1 below. These cooled combustion products flow through passage D--l into chimney flue -4.

It is evident from the foregoing that, during the operation in the direction detailed in the paragraphs immediately preceding the present one (i. e., air entering at valve V-2 and waste gases going to the stack through damper D-l and chimney flue C-l), the draftset up is in the direction from heating flue I, through flues 2, 3 and 4, to heating flue 5. at burner B-l, located at the turn between flues l and 2 (see also Fig. l), is deflected by the draft into flue 2. Similarly, the flames of burners 13-2, B3 and 3-4 are oven) of fiues 2 and 4 and at the pusher end of flues 3 and 5. 2and this applies as well to flue 4--is under the coke and the flue gets progressively less heat from burner B-| as one moves down toward the pusher end. Contrariwise, the hottest ends of flues 3 and 5 are those under the pusher end of the oven. while they'get least heat from burners B-'-2 and B-4, respectively, at under the coke end of the oven. It is obvious from this that flues 2 and 6 furnish most heat to the coke end of the oven on this run, somewhat less to the centre, and least to the pusher end, while flues 3 and 5 furnish most heat to the pusher end of the oven, somewhat less to the centre, and least to the coke end. Adding these two effects, the conclusion is arrived at that the sum of the heat furnished at any point along the length of the oven is about the same as at any other point, irrespective of the distance from the actual burners themselves. I

Upon a reversal of the draft, accomplished as described supra, with the preheated air entering at the coke end (with respect to the oven above) of flue 5, the flames of burners B-4, B-3, B-2 and Bl are deflected into flues 4, 3, 2 and I, respectively. In this case, the flames burn and at the coke ends of effect of each'individual flue upon the oven is to that detailed in the foregoing paragraph. The cumulative or additive effect of the whole series of flues beneath the oven, however, is exactly the same as in the other case. In other words, the heat furnished throughout a full cycle is practically uniform for the entire oven length, so that, with no black spots possible at the centres of the flues, there can be neither oven nor under- Moreover the reversal of 75 the flames, being deflected alternately from one down at reduced.

has pushed down the ends a flue into another, eliminates the'danger of hot spots.

When the regenerators R.i and R--2 are raised to the temperature necessary for preheating the air, the directions of 'flow of the air and the waste gases are reversed by opening damper D-2 and valve V--\ and closing damper Air then enters through in passase P-J being closed, upward through regenerators series, by means of the interconnecting passages P-6 to P-2, described supra, Passage then connects with heating flue 5. Al detailed immediately above, the flames are then deflected by the draft into heating flues 4, 3, 2 and I The waste gases flow downward through regenerat'ors RF! and R--4 necting passages P! to P--l6 ney flue C--2.

The operation of the valve boxes is clear from Figs. 7 to 10. In the position shown, cable C has the left, moving the straight arm of bell crank V--B in the same direction. The bell crank has turned shaft S-l to whichit is keyed. This movement of the shaft has raisedair valve V--2 from its seat. The curved arm of bell crank V-8 has been moved downward in an arc and upon adjustable rod SW3, which has in turn depressed lever V- i. Lever V-l has turned shaft 8-4, to which it is keyed, and this in turn has lowered damper D--2 into its seat. The travel to the right or the cable reverses this order, opening damper D-2 and closing air valve V-2.

The open position of the air valves V- -2 on the the battery is illustrated by Fig. 6, having traveled to the and through interconand so into chimwhich shows left. The arrangement of the damper boxes on.

time is depicted in closed.

the coke side at the same Fig. 5; air valves V- l being Stack draft is used for drawing air into the regenerators and for removing the gases o'tcombustion. The stack draft for each separatecoke oven is regulated by the position of the plate damper D-6. which is held in position in the passage to the chimney flue by quadrants Q. The air valves are equipped with air-regulating bars B, as mentioned supra. Bars B are removable, and the volume of air to each regenerator is controlled by the size and number of removable bars used to regulate the size of the opening into the body of the bOX (see Fig. 10).

In the operation of the oven as oven doors W-l and W--2 are closed and sealed air-tight, as may be seen from Fig.4. Coal is charged through the charging holes H in the top of the oven (see also Figs. 1 and 2), and the cone-shaped piles are levelled off in the usual manner 'by levelling ram K, introduced through a small door in the pusher side oven door W-2 (see Figs. 4 and 6). The charging hole covers N are replaced and sealed air-tight. Fuel gas is then burned with preheated air in the flues undemeath the coking chamber to provide a substantially uniform coking temperature for the entire area of the oven sole upon which the coal charge is supported. As is well known by those skilled in the art, the coking temperature varies whether low or high carboniza- Thus, a suitable temperature for low coking, such as about 600 to about 700 C., to a suitable temperature for high coking, for instance, about successfully used. Reversal periods 01 suitable 3 of the risers G| and through a special T, conveniently located in each Fig. 12,

tained by the coke oven art. 1 It will also be appreciated that, with for domestic us-esQ have an open, free-burning cell structure, and

y ovens have the great advantage of being adaptable to the production of either domestic or metallurgical coke.

has been dis- Its supply to the burners is regulated 1. A by-product coke oven or the broad rectanin said coked substantially uniformly. 2. A by-product coke oven gular sole-fired type which nately spaced from the ends of the oven to form a turn between any two adjacent flues thereby providing a single serpentine series-connected heating passage under substantially the entire sole area of said coking chamber, burning means located at the turns between adjacent heating flues and positioned in substantial alignment with the partition walls whereby flames issuing from said burning means can be deflected by a draft down either of said adjacent flues depending upon the direction of the draft therein, air inlets for supplying air to said burning means in said heating flues, a waste gas stack for removing products of combustion of said burning means from said heating flues, vertical regenerators located beneath the heating flues and communicably connected at opposite ends of the oven to the terminal heating flues in the series, connecting ducts communicating directly with the upper portions of said regenerators and connecting said regenerators to said terminal heating flues, and gas passages communicating with the lower portions of said regenerators and connecting said regenerators to said air-inlets and said waste gas stack, respectively, whereby a broad by-product coke oven is provided with substantially uniform heating conditions over the entire sole area of the coking chamber and whereby coal in said chamher is coked substantially uniformly.

3. A by-product coke oven of the broad rectangular sole-fired type which comprises a broad horizontal coking chamber having a sole thereunder and adapted to be sealed against the admission of air, a plurality of horizontal serially interconnected and interdependent heating flues having an odd number and arranged side by side underneath the sole of the chamber for heating it extending longitudinally substantially from end to end of the oven, longitudinal partition walls separating the fines from each other and alter nately spaced from the ends of the oven to form a turn'between any two adjacent flues thereby providing a single serpentine series-connected heating passage under substantially the entire sole area of said coking chamber, burning means located at the turns between adjacent heating flues and positioned in substantial alignment with the partition walls whereby flames issuing from said burning means can be deflected by a draft down either of said adjacent flues depending upon the direction of the draft therein, vertical regenerators located beneath the heating flues and communicably connected at their upper portions to the terminal heating flues in the series, two ducts one at each end of the oven communicably connecting said regenerators to said terminal heating flues, gas passages located below the regenerators communicably connected with the lower portions of said regenerators, and

valvular means in said gas passages to provide for alternately admitting air to be preheated to the regenerators and permitting exit of combustion products thereby providing for reversal of the direction of flow of hot gases through the heating flues, whereby a broad by-product coke oven is provided with substantially uniform heating conditions over the entire sole area of the coking chamber and whereby coal including culm waste and other low grade coals, peat, tar, lignitc, pitch, petroleum products including fuel oil and bunker oils, and the like in said chamber can be coked substantially uniformly.

4. A by-product coke oven of the broad rectangular sole-fired type which comprises a broad horizontal coking chamber having a sole thereunder and adapted to be sealed agair st the ad mission of air, a plurality of horizontal serially interconnected and interdependent heating flues having an odd number and arranged side by side underneath the sole of the chamber for heating it extending longitudinally substantially from end to end of the oven, longitudinal partition walls separating the flues from each other and alternately spaced from the ends of the oven to form a turn between any two adjacent flues thereby providing a single serpentine series-connected heating passage under substantially .the entire sole area of said. coking chamber, burning means located at the turns between adjacent flues and positioned in substantial alignment with the partition walls whereby flames issuing from said b'urning means can be deflected by a draft down either of said adjacent flues depending upon the direction of the draft therein, two series of vertical regenerators located beneath the heating flues and having inner portions of checkerbrick, two ducts each communicably connecting the upper part of a terminal regenerator of each series of regenerators with that end of a' terminal heating flue not directly conjoined with the adjacent flue, two gas passages communicably connected respectively with the lower part of the other terminal regenerator of each series of regenerators, and valvular means in said gas passages to provide for alternately admitting air to be preheated to the regenerators and permitting exit of combustion products thereby providing for reversal of the direction of flow of hot gases through the heating flues, whereby a broad by-product coke oven is provided with substantially uniform heating conditions over the entire sole area of the coking chamber and whereby coal in said chamber'is coked substantially uniformly.

5. A by-product coke oven of the broad rcctangular sole-.fired type which comprises a broad horizontal coking chamber having a sole thereunder and adapted to be sealed against the, admission of air, a plurality of horizontal serially interconnected and interdependent heating flues having an odd number and arranged side by side underneath the sole of the chamber for heating it extending longitudinally substantially from end to end of the oven, longitudinal partition walls separating the flues from eachother and alternately spaced from. the ends of the oven to form a turn between any two adjacent flues thereby providing a single serpentine seriesconnected heating passage under-substantially the entire sole area of said coking chamber, burning means located at the turns between adjacent heating flues and positioned in substantial alignment with the partition walls whereby flames issuing from said burnin means can be deflected by a draft down either of said adjacent flues depending upon the direction of the draft therein, two valve boxeslocated outside opposite ends of the oven, two series of vertical regenerators located beneath the heating flues and having inner portions of checkerbrick, two ducts each communicably connecting the upper part of a terminal regenerator of each series of regenerators with that end of a terminal heating flue not directly conjoined with the adjacent flue, two gas passages each communicably connecting the lower part of the other terminal regenerator of each series of regenerators with one of said valve boxes to cause air which is being heated to ascend and to cause waste gas which is being cooled to descend, two sets of valves each located I (SO in one of said valve boxes and adapted so to cooperate with each other that air to be preheated can be admitted in one valve box while combustion products are passing out of the other valve box and vice versa, and an automatic valveactuating means to provide such alternate cooperation thereby providing for reversal of the direction of flow of hot gases through the heating flues and regenerators, whereby a broad byproduct coke oven. is provided with substantially uniform heating conditions over the entire sole area of the coking chamber and whereby coal in said chamber is coked substantially uniformly.

6. The by-product coke oven construction as set forth in claim 5, wherein each valve box comprises a housing, an air inlet valve having a, port, slightly projecting shelves in said port adapted to support air-regulating bars whereby 1 thesupply of air to the heating flues can be controlled; a waste gas exit valve, and actuating ,means to cause said valves to alternate in operation whereby the air inlet valve is opened when the waste gas valve is closed and vice versa.

v'7'. A coke oven battery comprising a plurality of broad lay-product coke ovens arranged side by side each of which comprises a broad horij zontal coking chamber having a sole thereunder and adapted to. be sealed against the admission 1 of air, a plurality of horizontal serially interconnected and interdependent heating flues hav- 3 ing an odd number and arranged side by side underneath the sole -of the chamber for heating it extending longitudinally substantially from end to-end of the oven, long,itudinal partition walls separating the flues from each other and alternately spaced from the ends of the oven to form a turn between any two adjacent flues thereby providing a single serpentine seriesconnected heating passage under substantially the entire sole area of said coking chamber, burning means located at the turns between adjacent heating flues and positioned in substantial alignment with the partition walls whereby flames issuing from said burningmeans can be deflected by a draft down either of said adjacent flues depending upon the direction of the draft therein, two valve boxes located outside opposite ends of the oven, two series of vertical regenerators located beneath the heating .flues and having inner portions of checkerbrick, two ducts each communicably connecting the upper part of a terminal regenerator of each series of regenerators with that end of, a terminal heattingflue not directly conjoined with the adjacent flue, two gas passages each communicably connecting the lower part of the other terminal regenerator of each series of regenerators with one of said valve boxes to cause air which is being heated to ascend and to cause waste gas which is being cooled to descend, two chimney flues located below the regenerators and at the respective ends of the oven lying transversely with respect to the oven and extending from side to side and substantially -for the length of the battery to serve all the ovens the-rein each being communicably connected with the valve box at the same end of the oven, two

sets of valves each located in one of said valve boxes and adapted so to cooperate with each other that air to be preheated can be admitted in one valve box while combustion products are passing to a chimney flue through the other valve box, and vice versa, and automatic valve-actuating means to provide such alternate cooperation thereby providing for reversal of the directhe heating flue to the upper part of the regenerator connected with the valve box.

'9. A coke oven battery comprising a plurality of broad by-product coke ovens arranged side by side each of which comprises a broad horizontal coking chamber having a sole thereunder and adapted to be sealed against the admission i of air, a plurality of horizontal serially interconnected and interdependent heating flues having an odd number and arranged side by side underneath the sole of the chamber for heating it extending longitudinally substantially from end to end of the oven, longitudinal partition walls separating the flues from each other and alternately spaced from the ends of the oven to form a turn between any two adjacent flues thereby providing a single serpentine seriesconnected heating passage under substantially the entire sole area of said coking chamber,

burning, means located at the turns between adjacent heating flues and positioned in substantial alignment with the partition walls whereby flames issuing from said burning means can be deflected by a draft down either of said adjacent flues depending upon the direction of the draft therein, two valve boxes located outside opposite ends of the oven, two series of vertical regenerators located beneath the heating flues and having inner portions of checkerbrick and spacious chamber-like passages both above and below the checkerbrick in each regenerator thereby giving gases an opportunity to mushroom out before passing through and thus increasing the time of contact and affording more efiective heat transfer, two ducts each com municably connecting the upper part of a terminal regenerator of each series of regenerators with that end of a terminal heating flue not di' rectly conjoined with the adjacent flue, two gas passages each communicably connecting the lower part of the other terminal regenerator of each series of regenerators with one of said valve boxes to cause air which is being heated to asbend and to cause waste gas which is being cooled to descend, two chimney flues to a stack located below the regenerators and at the respective ends of the oven lying transversely with respect to the oven and extending from side to side and substantially for the length of the bat- I tery to serve all the ovens therein, each being communicably connected with the valve box at the same end of the oven, two sets of valves each located in one of said valve boxes and adapted so to cooperate with each other that air to be preheated can be admitted in one valve box while combustion products are passing to a chimney flue through the other valve box and vice versa, and automatic valve-actuating means to provide such alternate cooperation thereby providing for reversal of the direction of flow of hot gases through the heating flues and regenerators, whereby a broad by-product coke oven is provided with substantially uniform heating conditions over the entire sole area of the coking chamber and whereby coal in said chamber is coked substantially uniformly.

10. The by-product coke oven construction as set forth in claim 9 wherein each of the two series of regenerators comprises two vertical regenerators serially connected to each other from the lower part of the regenerator connected withthe heating flue to the upper part of the regenerator connected with the valve box.

11. The by-product coke oven construction as set forth in claim 9 wherein there are five heating fiues connected in series and wherein each of the two series of regenerators comprises two vertical regenerators serially connected to each other from the lower part of' the regenerator connected with the heating fiue to the upper part of the regenerator connected with the valve box.

12. In a by-product coke oven 01 the broad rectangular sole-fired type, the combination of a long horizontal coking chamber broader than its height, adapted to be sealed against the admission of air and having a sole thereunder; a plurality of horizontal serially interconnected and interdependent heating flues underneath the sole of the chamber for heating it, said fiues arranged side by side longitudinally of the chamber and each flue communicably connecting with the adjacent fiues on either side of it at alternate ends of the chamber respectively; and two series of vertical regenerators lying below and longitudinal of the heating flues and'communicabl'y connected therewith, each series of regenerators being adapted alternately to preheat air and interdependent heating flues underneath the sole of the chamber for heating it, said fiues arranged side by side longitudinally of the chamber and each flue communicably connecting with the adjacent flues on either side of it at alternate ends of the chamber, respectively, to form a turn between any two adjacent flues; two series of vertical regenerators lying below the heating flues and communicably connected therewith, each series of regenerators being adapted alternately to preheat air and to remove heat from hot products of combustion; burning means located at the turns between adjacent heating flues; risers communicably connecting said burning means with a fuel gas supply manifold; and means adapted to regulate the supply of fuel gas through each riser to the burning means with which said riser is connected, whereby the supply of fuel gas to each burning means can be independently regulated.

CHARLES H. HUGHES. 

